Improvement in botaey steam engines



Patented` Aug, 27,1867,

` S G HALL. RQTARY STEAM ENGINE;

- structed as and for the purpose described.

' sans 2 to keep the joints tight. The steam enters through the pipe f, and exhausts through the pipe g, er vice tersa, and from the steam and exhaust-ports extend recesses f g', which facilitate the entrance and thedischarge of the steam. These recesses may be protected by a screen or gridiron, with oblique or longitudinal bars, so that the rocking-heads e are prevented from catching in the same. The edges of the pistons work steam-tightagainst the inner surfaces of the cylinder-heads, and these heads areprovided with recesses [L to admit the solid ends of the piston-wheel, and-they are cast hollow or provided with steam-spaces z', so that the pressure of the steamon said heads is balanced, and the dishing out ofsthe heads ispreventcd. Without the steam-spaces the cylinder'- hea-ds are liable to dish out by th internal steampressure, and it is impossible to prevent leakage between the edges of the pistons. The shaft D has its bearings inrroller-boxes j in the cylinder-heads, and inside these rollerboxes are recesses 7c, to receive a metallic ring, Z, and packing-ring m. The metallic rings are faced perfectly truc, and aground joint is made between their inner surfaces and the vends of the piston-wheel. The packingrings m are made of India rubber orother elastic material, and by their action the metallic rings are pressed up against the ends ofthe piston-wheel, and the escape ot' steam is prevented. This mode of packing is very simple and effective, and it creates but very little friction, `when compared with the friction created by an ordinary stuinghox. To prevent the packing-ring m being blown out by the steam, the metallic surfaces between'which it is` held are provided with a series of V-groovcs, which clamp the packing-ring and hold itin position. vBy these means a rotary engine is obtained which works with great economy, and with comparatively little friction,

Whai'fI claim as new, and desire to 'secure by Letters Patent, is-

The L-shaped pieces of the piston B, provided with grooves d and tongues c, operating in combination with the' piston B', provided with recesses '6, when applied to the piston-wheel C and irregular cylinder A, all consAM. c. HALL.

-Witnesses A W. HA'UFF, C BERG. 

